Letters

Letters

Your Wish Is Our Command

I would love to see a detailed explanation on the new Completely Fair
Scheduler in the Linux kernel, including areas where it may be inferior
to the existing scheduler and where it excels. Also, I'd like to see an explanation of
the tickless patches, which apparently result in significant power savings.

—
Chris Thompson

We'll look into a scheduling article, but we have an article on power
savings in the works, including information on the tickless
patches.—Ed.

The Arcade Game Machine Is Hot!

I was very interested to read Shawn Powers' article on building an arcade
machine based around Linux [LJ, August 2007]. However, one thing that concerns me is the
lack of reference to cooling issues. If a PC is in a wooden box for
any period of time without a fan to force cool air through, there
would be a risk of heat damage to the machine, particularly the CPU and
the hard drive (www.coker.com.au/energy/computer-power.html).

The above URL has the energy use of some computers I have owned at various
times (the idle tests were idle at a Linux prompt—idle at a DOS prompt
or the BIOS uses significantly more power). You will note that a P4
machine uses significantly more power than a PIII. I can only guess at
the relative power requirements of a PIII and the original game hardware,
but I expect that all PCs manufactured in the last ten years use more
power and produce more waste heat. Even a PIII might have cooling problems!

One thing that is not widely known is that a P4 will generally take more
clock cycles than a PIII to complete a given amount of work—a 1.5GHz P4
will often deliver the same performance as a 1GHz PIII! If a machine is
to run in a poorly ventilated space, a PIII is a significantly better
option than a P4.

Hard drives take as much as 5W when idling. Use of other mass storage
devices (such as USB) might reduce the power use for such a machine.

I have a small stockpile of old PIII machines for occasions when I need
a low-power machine.

—
Russell Coker

The Inevitable Descent into Anarchy

The Linux OS is the most glamorous (I'm serious) example of [the] trend
[toward data anarchy], but Linux is only an outgrowth of a much bigger
universe of collaborative software development that uses open-source
licenses and techniques to leverage the talents and creative impulses
of hundreds of thousands of people worldwide. Cheap MP3 players and P2P
file-sharing networks are another.

Direct evidence of the trend is plummeting CD sales as users swap CDs,
copy new ones, file share and port their files to any device they
want. The efforts of the RIAA are becoming laughable, as they sue a few
unfortunates and scold the rest of the population from a position of
pious hypocrisy. They are the biggest thieves of all. Also pathetic are
the many pop stars, now grown rich and fat sucking on the corporate tit,
who parrot the RIAA's line. It matters not.

The only reason artists and record companies ever had control over music
media was that it was impractical for listeners to create their own. Given
that ability, most listeners will follow my own common-sense creed: when
I get the data, it's my data, and I'll do with it what I damn well please.

The RIAA hands down morality lessons while cracking the lawsuit whip
in hope of putting the file-sharing genie back in its bottle. They
pretend that there is some moral code that forbids consumers to copy
and give away music media. Their morality is based on laws that were
manufactured by a Congress eager to be bribed. It's easy to burst the
RIAA's moral bubble. Just travel back to 1850 in your mind and go hear
a music performer.

In 19th-century America, the artists played and the people enjoyed. It
had been that way for 10,000 years. If the artists were lucky or very
good, they could make a living by performing. Many do that to this very
day. It is an honest living. They work at what they love. It's their job.

It was a temporary quirk of technology that allowed artists and record
companies to turn performances into commodities to be bought and sold. A
few lucky artists could perform, record and then sit back and let the
bucks roll in while they snorted coke and bought mansions. That's OK with
me, and it still works for some. But, the data is written on the wall, and
it is an age-old warning that applies to all: adapt or die.

Readers may wonder what all this has to do with cell-phone networks. Carl
Brown suggested that there is nothing fundamentally blocking the concept
of a user-created cell-phone network. It also is true that there is
nothing blocking users from building their own worldwide data network,
uncontrolled by governments or corporations. If I can share my Wi-Fi
with the neighbors in my apartment, I can bridge to the guy across the
street who can run a directional shot to his buddy a quarter-mile away
who can...(ad infinitum).

The idea was not invented by me, although I humbly declare I thought of it
myself. The idea is so obvious, anyone with an understanding of networks
is likely to conceive of it. A quick Google search brings to light that
user-operated and user-supported community networks are already providing
free service to many people. The ISPs don't like it, but there's nothing
they can do about it. Those simple networks, however, are only attachments
to the Internet. They still depend on the corporate infrastructure.

Another and related sign of the trend toward anarchy is revealed in
the project called Netsukuku (netsukuku.freaknet.org). That project
community has created a dæmon that uses network interfaces to communicate
directly with the same dæmon in a connected computer. In theory, the
mesh network so created can mimic the Internet's TCP/IP layer with a
decentralized domain name system that uses distributed architecture and
builds routes that connect the computers attached to its network. It is,
as the creators say, anarchical.

I do not claim to see the future. I only extrapolate what seems to be an
inexorable transfer of communications and data management power from the
elite to the masses. If you believe in people, this can only be a
good thing. If you fear people, or begrudge them control over their own
lives, then you will fight it...and lose.

—
Tim Copeland

Practical Linux Box

I eagerly awaited the current issue of LJ [September
2007] to read the Ultimate Linux Box
article. I plan to build a system very soon and hoped to get some ideas.

Unfortunately, I just skimmed the article and was very disappointed. What
I really would like to see is a Practical Linux Box. No, your sidebar
“Penultimate” doesn't address my needs any more than the ULB. Your ULB is
really the Ultimate [Windows] Gaming Box, isn't it? For example, look at
the Display Card section. It's the latest and greatest DirectX 10 card?
How is this a good Linux box?

The things I'm looking for may not be what everyone else is looking for,
but I'd like to think there are enough people to warrant some practical
thinking in this type of article, such as:

Quiet/fanless power supply and case.

Small case with enough room for DVD and two hard drives.

Affordable: $2,000–$4,000 is not practical or affordable.

Onboard video is ok.

You could argue that I want a media PC, but that's not really my goal. I'd
settle for one. I'm estimating that I can build a system that fits the
above specs for about $700, without monitor. Other names for what I want
might be the Quiet Linux Box or the Affordable Linux Box.

—
JT Moree

The Ultimate Linux Box had nothing to do with Windows games or serving up
DirectX 10, which isn't even very useful on Windows yet. We'll consider
your desires for the next ULB issue though.—Ed.

Protection Money

I have to congratulate you on your /var/opinion “The Benevolent
Racketeer” [LJ, August 2007].

Your imaginary letter writer speaks right out of the soul of
everybody. The crowd reading the lines will equally agree and see their
points addressed as the crowd reading between the lines. Luckily, I paid
my insurance money to Linux Journal, so you will not sue me for reading
this terrific piece of word code.

—
Kurt

mkdir Errors

I too have a small nit to pick with respect to sample code and the lack
of error handling. It is trivial to add at least some minimal error
handling. In the September 2007 issue's Letters, Jack points out that mkdir error
handling is non-existent. Bash scripts are notorious for not doing any
error handling. As for the mkdir issue that Jack points out, I would
suggest the following:

The -p switch to mkdir will create all directories in the
$dimension string recursively and will not complain if any or all directories
already exist. The main reason for failure will be user permissions.
This is handled by echoing the error and returning an error value to
the caller.

If the goal of these sample scripts is to instruct beginners to learn
techniques with bash, error handling cannot be ignored. The same
goes for Ruby, Python, Perl, C and C++. The code samples in the SCTP
(why does that make me think of John Candy) article are excellent in
this regard.

—
steeve

Ultimate PVR

I enjoyed your article in the September 2007 issue of
LJ about the woes of cable TV and
implementing a PVR for HDTV [see Nicholas Petrelely's /var/opinion].

I'm such a huge fan of PVRs, and I've had them for five years now with DishNetwork. Your
article praised TiVo's PVR product, talking about ergonomics, and they
do make a nice setup. They were the pioneers of the technology.

If you haven't used the DishNetwork HDTV box, give it try sometime, if
you know anyone that has one. I'm absolutely blown away with all the
trick things you can do with that box. You'll want one if you're as gaga
about technology as I am. It's far better than my neighbor's DirecTV PVR by
a longshot. I could fill this page with the things DishNetworks 622 box
will do, but I won't bore you. The nuance you mentioned about
TiVo predicting where you want to go when you push Replay—that's just
the beginning for Dish. It's amazing how navigation ergonomics makes
such a difference in this kind of an appliance, making what “could
be”
a complicated device very simple to use. I do like the
DirecTV capability to set bookmarkers in each recording—that's cute,
but it's not as valuable as all the other things Dish does.

Next year, we should talk about Datalight's (the company I work for)
support for Linux. We will be offering some new capabilities for
mobile Linux devices that you might be interested in learning about.
Our Linux support is about two months away, so January 2008 should be good timing.
I'll suggest to our marketing folks that they should get in touch with you to possibly
do an article.

—
Tom Spurlock

Coincidentally, thanks to moving out into the country, I now use a
DishNetwork HDTV, which I am told is based on Linux. I'll be writing
about it soon.—Ed.

Comment viewing options

Usoft does it again,
my Internet Supplier (Bell Canada) uses MSN as it's carrier, and because of e Internet Supplier (Bell Canada) uses MSN as it's carrier, and because of this I got the followingresponse when asking to access a chat line on MY supplier, re info for MY n ME BUYING more service from them.................................

""" Chat support requires a Microsoft® Windows® operating system and Internet Explorer 5.5+.
The Macintosh operating system, Netscape, Firefox and Safari browsers are not supported.
To get more help, call 310-SURF (310-7873). ""

I may talk funny (I'm from Scotland originally) but that don't make me stupid eh........

Why is that we in North America allow this man (wee willie gates) to run monopolyshod over us, at least in the EC they give him a hard time. Are the Canadian and the American Govs so taken with this man's charm that they fall flat on their collective faces in adoration eh!!!!!!!!!!!!! ????

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